What kind of pet would you like to have? Why? 

I like cat.because cat is so cut. --> I like cats because cats are cute. => Corrected : The sentence is corrected grammatically.

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How was your vacation?   ✔

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I was great.  --> It was wonderful. 

to blow one's nose. --> blow your nose.  

=> Your sentence has a correct grammatical structure, but this has the correct usage/ expression.

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